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Cammenga 3H Mil-Spec Compass


3H2cIn the past 4 years I’ve been through quite a few compasses.  They’re not something I use a lot, and not something I know particularly that much about, but they are an absolute necessity for outdoor enthusiasts.  I’ve been through a handful of cheap ones, as well as several costly ones from famous manufacturers and haven’t quite had one that worked out for me.  This is mostly because of the environment my compass is subjected to.  I live at 6,600 ft elevation and work at 8,150 feet above sea level.


I often camp and hike at 9,000 to 10,000 ft, and have hunted above 10,000 ft on several occasions.  Absolutely anything under any type of pressure is pushed within an inch of its life at these elevations.  When I moved to the mountains from sea level, I owned a very nice liquid filled compass that had provided several years of excellent service.  A short time after the move, it developed a bubble so large the needle would no longer turn.  I decided to purchase a compass that was sold at elevation, thinking if it made the trip up here and sat on the shelf, it would survive.  It was a popular model from a reputable company.  I now have two nice baseplates with non-functioning needles.   After that, I quit using compasses for a while.

3H1aA recent unplanned work trip into the backcountry convinced me I needed to revisit the compass issue.  (Another lesson learned was ‘always carry your personal survival kit’, but that’s another article….)  I’m frequently, along with my equipment, exposed to temperatures well below freezing.  Single digits are the norm in the winter, and negatives overnight are regular.  I needed a compass that would hold up to changes in altitude from sea level to 12,000ft, and a temperature range from 100F to -20F.  Those are the conditions I’m frequently outdoors in, so that’s what was required.  Enter the Cammenga 3H Mil-Spec compass.

Minus a few markings that are military specific, the 3H is the same compass issued to US Military troops.  It’s a lensatic design, so no fluid to bother with.  It’s also vacuum-sealed, so pressure changes don’t matter at all.  The compass capsule is waterproof, and good down to -50 degrees.  It’s plenty robust for me.  Altitude, dust, grime, moisture, and trail gunk just roll off of its back. It’s tough too, built into an aluminum housing that closes completely around the compass capsule.

3H3aThe markings are Tritium gas filled tubes.  Tritium glows constantly, with no need for an exterior light source.  They say it’ll glow for a minimum of ten years, and since my Cammenga was manufactured in 2009, I’m not worried about it going out any time soon.  If you don’t need the tritium, or need to save a few bucks, Cammenga makes the compass exactly the same with the replacement of phosphorescent paint at the markings instead of tritium.  Otherwise it’s the same animal.  But I’m very happy I splurged and went with the tritium model.  I was pleasantly surprised when I first used it at night.  The tritium glowing capsule under the compass disk allows you to not only see the directionals, but to also accurately read a bearing without the need of a flashlight.  The directional disk is essentially backlit at the sighting line with a tritium tube under it, illuminating it from below.  That’s a very nice feature.  The disk is also graduated in Mils and Degrees, making easy use of whatever bearing or measurement you have a need for.

A lensatic compass doesn’t have any fluid to ‘dampen’ the needle.  Dampening is just a fancy word for stopping the needle from swinging and getting it to settle down and indicate direction.  The Cammenga directional disk is copper induction dampened.  Now, I don’t know much about copper induction dampening, but I do know that the military required that the disk settle down and indicate direction in 6 seconds or less.  My Cammenga does this easily.  And since the needle (which the directional disk is attached to) rotates on a jeweled sapphire bearing, the disk movement is smooth and fast.  Another winning element to the Cammenga is that when it’s closed, the directional is slightly lifted up and off the bearing, locking it into a fixed position.  This prevents the needle from beating and banging around inside the compass during carry or transport.  The fact that the needle is kept secure inside the compass housing undoubtedly contributes to the Cammenga’s durability.

3H4aSighting a heading with the 3H is super simple.  Open it properly and hold it up to eye level.  Look through the sighting notch and line up a distant object with the sighting wire.  Then look through the magnifier and read the bearing.  If you need to travel a known bearing, simply line that up first, and then sight on a distant object.  Very simple, quick, and accurate.  The Cammenga 3H doesn’t have a clear baseplate, but in use, I haven’t missed it.  Instead of laying your compass on your map over the direction you intend to travel, you just open the compass flat and lay it beside the intended direction (azimuth, bearing, or etc.).  The straight, graduated edge of the fully opened compass case is then used to find an azimuth the same way a clear baseplate compass is used.  During use, magnetic declination must be manually accounted for.  Where I live has a 9° east magnetic declination, easy to account for and not a big issue in use.  Depending on where you live, or travel to, and if you plan on navigating extensively from maps, you’ll need to do your own research about your magnetic declination.

3H5aNeedless to say I’m very impressed with the 3H.  Although it is bulkier and a bit heavier than most compasses, I feel the durability and quality more than make up for it.  I’ve been using it for six months or so and have found myself sighting and taking bearings on tons of objects just for fun.  Sighting down the side of my house, it faces exactly 240 degrees.  I’ve used the 3H hunting and hiking as well, and have enjoyed it.   The tritium version is available for just under $80, while the phosphorescent version can be found as low as $45. I’m certainly no compass expert, but I’m happy with this one.  Great piece of kit! 



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